Neuromuscular electrical stimulation of humeral adductors in subjects with rotator cuff tear.

INTRODUCTION: In symptomatic patients with rotator cuff tear, MRI and radiographic studies have ascribed the pain symptom to insufficient humeral head depression during arm elevations. The arm adductors such as the teres major and pectoralis major may contribute to depression of the humerus head during arm elevations. Researchers have demonstrated that neuromuscular electrical stimulation (NMES) of the serratus anterior and lower trapezius can control scapular motions and improve acromiohumeral distance. It is unknown, however, if adductor neuromuscular training could help patients with rotator cuff tear. MATERIALS AND METHODS: A cross-sectional study of NMES of the teres major and pectoralis major was conducted on 30 symptomatic subjects with rotator cuff tear. We measured the acromiohumeral distance by ultrasonography and scapular kinematics during arm elevation with a three-dimensional motion tracking system. RESULTS: The acromiohumeral distance significantly increased during NMES of the teres major (0.73 mm, p < 0.001). However, the distance significantly decreased with NMES of the pectoralis major (0.78 mm, p < 0.001). Additionally, scapular upward rotation was greater during NMES of the teres major than during NMES of the pectoralis major (3.4°, p < 0.001). Scapular external rotation decreased significantly more during NMES of the pectoralis major than during NMES of the teres major (1.6°, p = 0.003). CONCLUSIONS: NMES of the teres major can increase acromiohumeral distance and scapular upward rotation during arm elevation. However, the decreased upward and external rotation of the scapula during arm elevation with NMES of the pectoralis major may be associated with subacromial impingement.

Pitching Biomechanics and Shoulder Function in Baseball Pitchers with Scapular Dyskinesis.

The primary purpose was to investigate the influence of scapular dyskinesis (SD) on pitching biomechanics and shoulder function in high school baseball pitchers. The secondary purpose was to identify possible factors associated with shoulder function in pitchers with SD. Thirty-eight pitchers were classified into the SD group (n=26) or the non-SD group (n=12). They were evaluated with the Kerlan-Jobe Orthopaedic Clinic shoulder and elbow (KJOC) scale and clinical measurements of shoulder characteristics, and with measurements of scapular kinematics, muscle activation, and ball speed during fastball pitching. Compared to the controls, the pitchers with SD had less scapular external rotation (difference=11.3 degrees, ES=0.92, p=0.012) during overall pitching and less upper trapezius (UT) activation during the late cocking (difference=7.1%, ES=0.79, p=0.019) and acceleration phases (difference=12.5%, ES=0.75, p=0.035). Higher UT activation during the late cocking phase was significantly associated with higher KJOC scores (standardized ß=0.415, p=0.039). In conclusion, deficits in scapular external rotation and decreased UT activation during pitching were found in pitchers with SD. Higher UT activation may be important for shoulder function in pitchers with SD.

Glenohumeral Internal Rotation Deficit on Pitching Biomechanics and Muscle Activity.

To characterize the scapular pitching biomechanics in symptomatic GIRD pitchers (SG) compared to asymptomatic GIRD (ASG) and healthy pitchers. The scapular kinematics and associated muscle activities during pitching were recorded in 33 high school pitchers. Compared to healthy, GIRD pitchers had less scapular posterior tilt in each pitching event (average difference, AD=14.4°, p<0.01) and ASG demonstrated less scapular upward rotation at ball release (AD=12.8°, p<0.01) and greater muscle activity in the triceps brachii in the early-cocking phase (AD=9.9%, p=0.015) and in the serratus anterior in the late-cocking phase (AD=30.8%, p<0.01). Additionally, SG had less muscular activity on triceps brachii in the acceleration phase and serratus anterior in the cocking phase (AD=37.8%, p=0.016; AD=15.5%, p<0.01, respectively) compared to ASG. GIRD pitchers exhibited less scapular posterior tilt during pitching, which may cause impingement. Since tightness of the anterior shoulder is a common cause of inadequacy of posterior tilt during arm elevation, stretching exercise of the anterior shoulder is recommended. Given the inadequate recruitment during pitching in the GIRD pitchers, symptoms may develop following potential impingement.

Author Correction: Rapid Staining of Circulating Tumor Cells in Three-Dimensional Microwell Dialysis (3D-µDialysis) Chip.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

Rapid Staining of Circulating Tumor Cells in Three-Dimensional Microwell Dialysis (3D-µDialysis) Chip.

The conventional techniques to detect circulating tumour cells (CTCs) are lengthy and the use of centrifugal forces in this technique may cause cell mortality. As the number of CTCs in patients is quite low, the present study aims towards a gentler diagnostic procedure so as not to lose too many CTCs during the sample preparation process. Hence, a Three-Dimensional Microwell dialysis (3D-µDialysis) chip was designed in this study to perform gentle fluorescence-removal process by using dialysis-type flow processes without centrifuging. This leads to a minimum manual handling of CTCs obtained in our study without any contamination. In addition, a rapid staining process which necessitates only about half the time of conventional techniques (35 minutes instead of 90 minutes) is being illustrated by the employment of dialysis process (by dynamically removing water and waste at once) instead of only static diffusion (by statically removing only waste by diffusion). Staining efficiency of our technique is improved over conventional staining because of the flow rate in 3D-µDialysis staining. Moreover, the staining process has been validated with clinical whole blood samples from three TNM stage IV colon cancer patients. The current technique may be termed as "miniature rapid staining and dialysing system".